To pontificate is to express your opinion in an annoying way, often because you go on too long or because you are too much of a know-it-all.(verb)
An example of pontificate is the actions of a self-important professor who rambles on and on.
See pontificate in Webster's New World College Dictionary
Origin: L pontificatus < pontifex: see pontiff
See pontificate in American Heritage Dictionary 4
Origin: Latin pontificātus
Origin: , from pontifex, pontific-, pontifex; see pontifex
Origin: . V., from Medieval Latin pontificāre, pontificāt-, to act as an ecclesiastic
Origin: , from Latin pontifex.
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